Spark-plug.



A. R. MEACHAM.

SPARK PLUG. l APPLICATION FILED FEB. 27, 1911.

Patented 11611.21, 1911.

A the outer or `electrode' illustrated in' ALDAH ROBINSON MEACHAM, OF

f si enr entre. y

OKLAHOMA, OKLAHOMA, ASSIGNOR OF'ONE-HALF TO `CHARLES G. FROST, OF OKLAHOMA, OKLAHOMA..-

' sfu/mienne.- l

serial No. 611,257:

To all whom: if may concern:

'Be it known that I', Ailnii RoBrNsoNy Manci-mina citizen of the United States, re-t .siding at Ol lal1ona, co u'nty of Oklahoma,

and State of Oklahoma, have invented cer tain new and useful Improvements in Spark- Plugs, ofwhich the following is a specifica! tion.

My 'invention relatesl to spark plugs fori internal combustion engines, and the' object? of my invention is to provide a spark plug o f'i'the class'mentioned which may be readily cleaned'without removingthe4 plug from the engine and that'while the engine is in operation.

A further object of my' invention is to provide a spark plugin which thesparking distance between the electrodes may be adjus'ted while the enginei's running.

Other objects'wi appearhereinafter.

My invention willbe more readily understood by reference 'to the accompanying drawings .formin' a part o f this specification an'din whicligf .Figure 1 is a vertical central section of 'a sparking plug embodying my invention in its preferred form, Fig. 2 is a plan view of the same, Fig. 3 is a bottom plan View of the lower portion of the plug illustrating a modified form of the electrodes5 Fig. 4- is av similar view illustrating a modified form of; y permanently stationary, elec-5 trode, Fig. 5 'is afsiinilarvie'w illustratingv al modified' form offthe`inner or .movable electrodeyFig'. 6 is a pers ec'tive view of thel ig. 5,*Fig. 7 is a' horizontal section taken on the line -m` of Fig. 1, Fig. Slis an elevation of the upperf end of the insulating sleeve, 4and Fig. 9 4is anelevationof-the cleaning device." Referring now tto the drawings 1 indi-5 ca tes metal bushing provided with a r'educd'th'readed' portion 2'which is adapted 'to^be' tappedinto' the wall 3 of'an engine cylinder. The body 1 externally squared to form a wrenchhold and is provided witha threaded' socket 4. The extension 2 is formed with a smooth cylindrical socket 5 of less diameter than'thesocket 4`and eX-' tending from the socket'4'th'rough`the lower end of the bushing.- 64 indicates a .poreelgin .insula-ting sleeve- Icomprising a lower cylindrical portion 7 it- .ting snugly within the l socket 5 and :1n-upper conical portion 18,- which projects considerf 22 and .interposed between said header butably above the bushing and terminates at its upper end in cylindrical portion l9. YThe base of the 'portion 8 is of greater diameter than that of the portion 75 forming anan'nular slioulder'l() which rests upon thebottom of the socket 4 with a gasket 11 interposed between said shoulder and soclget bottom. Tie gasket is preferably 'formed Ofcompressible' material. 5 l

12 indicates a sleeve threade'd into vthe socket 4l and .provided with a conical bore fitting snugly about the adjacent portion of the member 6. The upper end of the sleeve 12 is'squared as at'13 t`o afford a wrench hold. It 'is obvious thatbyturning the sleeve 12 them'ember 6 will be'rmly secured in the bushing and suiiicie'nt pes'surermay be had upon thel gasket 11"to form a tight j'int.,

.Theupper end "9 of the member disprovided with a peripheral groove' or'socket 14.- in which rest semi-cylindrical members 15 the outer faces of which' are threaded' as shown. A d

16 indicates a vertical rib or boss extending from top to bottom. of the groove 14 and projecting between the ends of the members 15 to prevent` rotation o f the same in the groove. There may be one or two of the ribs 1G as` desired vand in Fig. 7 have'illlustrated two. Threaded uponthe member 15 is'a cap 1'7 :which is provided upon one side with a binding post 18. Extending longitudinally' through the member 6 and through the cap'l'is a rod 19, the lower end of Vwhich is provided'with the movable electrode 20.

21findicates the stationary electrode provided up'onlthe lower end ofthe portion 2 of the bushing. The upper end of the rod 19`is provided with a head orpush button ton and the cap 17 is a spring -By pressing Aon the head 22 the rod `19 may be depressed. and when releasedthe spring will return thel same to normal position.; 'The member (his provided with' a cylindrical longitudinally' exten ding passage way 24 terminating atthe lower end'in'a recess 25 of greater diameter and extending inwardly from the lower end the member 6 and concentric'with'the rod 19. Arranged within the recess 25 and fixed to the rod 19, is a piston 2G provided -withaspring expansion ring 27 which frictionally engages the walls of -the recess 25 at all times. Depending from the periphery of the piston is a cylindricalsheet metal shell or scraper 28 which is longitudinally split as at` 29 and normally fiared. This is compressed within the recess 25 and bears firmly against the Walls thereof.

.It is obvious that ly depressing the rod 19 the carbon deposit which forms at the end of the plug adjacent the electrodes will be readily removed by the piston and scraper,

and that the cleaning of the device may bev accomplished whilel the engine is ruiming. 30 indicates a shellacked leather washer interposed between the end of the member 6 and the cap 17.' Fixed' to the rod 19 and forming'a stop to 'limit the u ward movement thereof is a ball v3l whlch normally rests in a cylindrical seat 32 in the cap 17 and thus forms a valve to prevent leakage through the cap 17 about the rod 19. It

. should be noted that the passage way 24 is of greater diameter than thatof the ball valve 31.

The electrode 2O is eccentricallv mounted upon the end of the rod-19 so that by turning the rod the spark gap may be varied.l Fixed to the head 22 is a spring arm comprising a.

horizontal portion 33 and a vertical portion 34, the latter terminating at its 'lower end in la well rounded portion 35. The cap 17 "and the rod turned. until it rests in one of 35.'

the other grooves. By this construction the rod may be turned to varythe spark gap and lock in adjusted position, and at the same time leave the rod free for vertical reciprocation'. 'Further the spark lgap may be varied while the engine is running.

In the drawings I have illustrated several forms of electrodes, but in each the electrodes comprise a stationary electrodeand a movable electrode of such construction and* arrangement that by rotating the latter the space. or gap between them is varied. In Fig. 1 the stationary electrode comprises a bent tongue formed integral with the member 2 and the movable electrode comprises 4a disk eccentrically mounted on the end of the rod. As shown in Fig. 3 the end of the rod 19 is bent at right angles as at 18 to form the movable electrode and the stationary electrode may partake of the form shown in Fig. 1 or may bea bent rod 19a having one end fixed in the member 2. In Fig. 4 the stationary electrode comprises a fiange 19b formed integrally with the member 2 and having an eccentric concave inner edge 19,

the movable electrode being preferably the form shown in Fig. 3. It is obvious that by turning the rod 19 the end of the electrode v 18a will be moved closer to or farther from the edge 19c as the case may' be. In Figs. 5 and 6 I haveshown a modified form wherein the stationaryl electrode partakes of. the form shown in either Fig. 1 or Fig. 3, and the end of the rod 19 is rbent to form an eccentric arc 18b which constitutes the movable electrode. The rod 19 is first bent radially outwardly and then curved to form the arc, the are 18b being in aplane at rightl angles to the rod.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1; In a spark plug, a bushing, a porcelain insulating sleeve arranged in said bushing and provided with a recess in the inner en thereof, a rod extending through said sleeve and recess, anelectrode on said bushing adjacent the lower end of said sleeve, a second` electrode on the inner end of said rod, a' piston within said recess and fixed to said rod,

a depending peripheral scraper on said piston, a head on said rod and a spring interposed between said head and said sleeve, substantially as described.

2. In a spark plug, a bushing, a porcelain sleeve fixed within said bushing and proj ecting above the sameLa cap fixed to the upper end of said sleeve, a rod extending through lsaid sleeve and said cap, an electrode on t e inner end'of said rod, an electrode on the adjacent end of said bushing, said' electrodes being eccentricall'y arranged with` relation to ea'ch other, a head on the outer end of said rod, a spring interposed between said head and said cap, said cap being provided on its periphery with a plurality of vertically disposed grooves and a spring arm fixed to said head and having a portion adapted to engage either of said slots for vertical reciprocation therein, substantially as described.

In a spark plug, a bushing, an insulating sleeve in said bushing, a rod extending through said sleeve and rotatably mounted therein, a radially extending electrode on the end of said rod and a iixed electrode on said bushing comprising an inturned fiange' having an eccentric concave edge, lsubs'tanj tially as described.

In testimony whereof I- have signed my name to this specification in the presence of two subscribing witnesses.

ALDAH ROBINSON MEACHAM.

Witnesses:

ALDoN GUTHRIE, i W. D. CARDWELL. 

